Chuck



2,117,746 RIGHT) May 17, '1938.

ROY M. SIEAWRIGHT (ROBERT MORTON FELIX SEAW CHUCK m 9 ,y 7 W, 0 m

INVENTQR Meaww'y/l HI 5 ATTORNEY.

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Patented May 17, 1938 UNITED STATES PATENT OFFlCE rica, assignor to Ingersoll-Rand Company, J ersey City, N. J.,

Application June 25,

6 Claims.

This invention relates to gripping devices, and more particularly to a chuck adapted to be attached to the body of a working implement, as for instance a drill steel.

One object of the invention is to enable the chuck to be readily attached to and detached from the working implement, and another object is to assure a firm gripping action of the chuck on the working implement.

Further objects will be in part obvious and in part pointed out hereinafter.

In the drawing accompanying this specification .and in which similar reference numerals refer to similar parts,

Figure 1 is an elevation, in section, of a chuck constructed in accordance with the practice of the invention and showing it connected to a working implement and an actuating device, the latter being partly broken away,

Figure 2` is .a transverse view taken through 0 Figure 1 on the line 2-2,

Figure 3 is an elevation, in section, of the casing of the chuck, and

Figures 4 and 5 are perspective views of details.

Referring more particularly to the drawing, 20 designates, in general, a chuck constructed in accordance with the practice of the invention and 2| a working implement to which the chuck 2|] is .grippingly connected. 22 designates a driving element for imparting a force through the chuck 26 to the working implement 2| for freeing the latter from the material binding it in the drill hole 23.

The driving element or motor 22 selected for the purpose of illustration is of the type illustrated in United States Patent No. 2,012,916, granted to R. H. Pott, August 27, 1935, and to which patent access may be had for a full understanding of the nature of the driving elementl 22. It may, however, be explained in connection with this description that the driving element 22 embodies in its organization a driving head, designated herein 24, which is rotatable in a casing 25 and has shoulders 26 enageable by shoulders 21 on a hammer element 28 rotated by a suitable motor (not shown).

As explained in the patent, the driving connection between the motor and the hammer 28 includes a flexible element (not shown) which transmits the rotative movement of the motorv to the hammer 28 and tends constantly to maintain the shoulders 21 in interlocking engagement with the shoulders 26, but is capable of endwise contraction so that, in the event of undue resistance to rotative movement, the shoulders 21 will rea corporation of New Jersey 1936, Serial No. 87,157

main momentarily stationary with respect to the shoulders 26 while the torque of the driving motor causes contraction of the flexible element and, therefore, withdrawal of the shoulders 21 from the shoulders 26. In this way energy is stored 5 in the flexible element and expended as a torsional force against the shoulders 26. Thus, the driving head 24 is subjected intermittentlyto torque and to sharp impacts for releasing the working implement 2 I.

The chuck 2U, in the form illustrated, comprises a casing 29 which is split longitudinally to divide it into a pair of half sections 3D of which the confronting surfaces 3l are held in body contact with each other by a series of rings 32, 33 and 34 encircling the sections Sil .at rear, intermediate and front portions, respectively, to bind the sections 3l) securely together. i

The casing 30 is recessed interiorly to provide a bore 35 which extends entirely through the cas ing. The forward portion of the bore 35 is in the form of an enlarged portion 36 to receive gripping elements or jaws 31 adapted to grip the working implement 2l. The jaws 31 are disposed loosely in the portion 36 of the bore so that they may move freely longitudinally therein and have internal recesses 38 conforming substantially to the contour of the working implement which they are intended to grip. On the exteriors of the jaws are coniform surfaces 39 which conform with and are adapted to frictionally engage a coniform surface 4l) constituting the foremost portion of the bore 35.

The rearmost portion of the enlarged end 36 of the bore is preferably of cylindrical shape to accommodate a plate 4| formed in half sections 42. The sections 42 have lugs 43, at the points of juncture of the sections, which extend into recesses 44 in the surfaces 3| of the casing sections 36 to form an interlocking connection between the plate 4| and the casing 36 and thereby prevent relative rotary movement between these elements. The plate 4| seats against the rear or end wall 45 of the portion 36 of the bore and carries on its front end curved or partly annular ribs 46 of which the front surfaces are inclined to provide cam surfaces 41 adapted to engage similar cam surfaces 48 on the rear ends of arcuate ribs 49 carried by the jaws 31.

The portion of the bore 35 lying rearwardly of the portion 36 and designated 56 is preferably of only slightly larger diameter than the maximum cross sectional dimension of the working implement, which extends into the portion 5|). Intermediate the ends of the portion 50 of the bore is a stop member 5| which serves to limit the distance which the working implement may extend into the chuck. 'I'he portion of the bore 35 lying rearwardly of the sto-p member and designated 52 is shaped to conform to a stem 53 carried by the head 24. The stem 53 extends into the bore 52 and, in the present instance, is provided with depressions 54 for the accommodation of the ends of set screws 55 threaded into the ring 32 and the casing sections 3B to secure the chuck to the stem 53.

'I'he operation of the device is as follows: Whenever the working implement 2l becomes rstuck in the drill hole 23, as when a collar of detritus accumulates around its cutting bit and bonds it to the wall of the drill hole, the rock drill actuating the working implement is removed from the working implement and the chuck 20, with the driving element connected thereto, is placed on the end of the working implement.

When the driving element 22 is set in operation its initial rotary movement imparts a similar movement to the chuck and, since the jaws 3l are interlockingly engaged with the working implement, the chuck casing will, therefore, also rotate relatively to the jaws. This movement of the chuck casing causes the cam surfaces 4l to slide over the cam surfaces d3, assuming, in the structure illustrated, that the driving element operates to rotate the head 2G in a clockwise direction as viewed from the operators position, and actuate the jaw members 3l axially forward toward the open end of the bore.

The thrust thus imparted to the jaws forces vthem into tight gripping engagement with the working implement. At the same time the coniform surfaces 39 are pressed into rm frictional engagement with the coniform surface i so that the jaws and the casing will also be locked together. Subsequent operation of the driving f Adevice subjects the driving head 2li to torque and impact, in the manner hereinbefore described, and these forces will loosen the working implement from the material binding it in the drill hole.

Inasmuch as the driving element and the working implement are connected firmly together a constant pull may be applied to the driving element by the operator during the operation of the driving element. This force, together with the forces delivered by the driving element, invariably suice to quicldy loosen the working implement. After the working implement has been freed the chuck may be rotated in anti-clockwise direction and the cam surfaces 4l thereby moved out of engagement with the cam surfaces G8. In this way the jaws 3'! will be released from the working implement and the coniform surface 40 and the working implement may then be conveniently removed from the chuck.

I claim:

1. A chuck, comprising a casing having a bore to receive an instrument, gripping means freely movable longitudinally in the bore, surfaces on the gripping means and in the bore adapted to frictionally engage each other, and means on the frictional engagement upon relative rotary movement between the casing and gripping means.

2. A chuck, comprising a casing having a bore, an inclined surface in the end of the bore, a gripping device in the bore and having an inclined surface to engage the rst said surface, and means on the casing extending longitudinally into the bore separate from the gripping device and the casing to push and impart gripping movement to the gripping means and effect rm frictional engagement between the inclined surfaces upon relative rotary movement between the chuck and gripping device.

3. A chuck, comprising a casing having a bore, jaws in the bore, inclined surfaces on the ends of the jaws and in the bore cooperating with each other to effect gripping movement of the jaws upon axial movement of the jaws within the bore, and ribs on the inner ends of the jaws and the adjacent portions of the casing having inclined surfaces to cooperate with each other to effect such movement of the jaws and to effect rm frictional engagement between the first said inclined surfaces upon relative rotary movement between the jaws and the casing.

4. A chuck, comprising a casing having a bore, a coniform surface in the bore, jaws in the bore having coniform surfaces to frictionally engage the coniform surface in the bore, cam surfaces on the ends of the jaws, and plates in the end of the bore interlocked with the casing and having cam surfaces to engage the rst said cam surfaces upon relative rotary movement between the jaws and the said plates for pressing the jaws into frictional engagement with the coniform surface of the bore and to impart gripping movement to the jaws.

5. A chuck, comprising a casing formed in a plurality of sections and having a bore extending therethrough, means to secure said sections together, a coniform surface in the bore, jaws in the bore having coniform surfaces to frictionally engage the coniform surface in the bore, cam surfaces on the jaws, cam members in the bore to engage the cam surfaces for pressing the jaws into frictional engagement with the coniform surface of the bore and to impart gripping movement to the jaws upon relative rotary movement between the casing and the jaws, and means on the cam members interlockingly engaging the casing to preventV rotary movement of the cam members with respect to the casing.

6. A chuck, comprising a casing formed in a plurality of sections and having a bore extending therethrough, rings encircling the sections for binding said sections together, a coniform surface in the bore, jaws in the bore having coniform surfaces to frictionally engage the coniform surface in the bore, cam surfaces on the innermost ends of the jaws, plates in the bore having cam members to engage the cam surfaces upon relative rotary movement between the casing and the jaws for actuating the jaws axially of the bore and thereby impart gripping movement to the jaws and cause the coniform surfaces of the jaws and the bore to frictionally engage the casing, and means for securing the casing to a chuck driver. 

